Capacitor comprising anti-ferroelectric layers and high-k dielectric layers

Abstract

A semiconductor device includes a first electrode, a second electrode, and a multi-layer stack positioned between the first electrode and the second electrode, the multi-layer stack including at least one anti-ferroelectric layer and at least one high-k dielectric layer.

What is claimed is: 
     
       1. A semiconductor device comprising:
 a capacitor, wherein the capacitor includes: 
 a first electrode; 
 a second electrode; and 
 a high band gap layer disposed between the first electrode and the second electrode; 
 a first high-k dielectric layer disposed between the first electrode and the high band gap layer; 
 a first anti-ferroelectric layer disposed between the high band gap layer over the first high-k dielectric layer; 
 a second high-k dielectric layer disposed between the second electrode and the high band gap layer; and 
 a second anti-ferroelectric layer disposed between the high band gap layer and the second high-k dielectric layer, 
 wherein the first and second anti-ferroelectric layers have a tetragonal crystal structure, 
 wherein the first and second anti-ferroelectric layers include a hafnium oxide-rich hafnium zirconium oxide whose hafnium oxide content is greater than a zirconium oxide content, 
 wherein the high band gap layer is formed of a single layer of an aluminum-containing material and is directly contacted with the first and second anti-ferroelectric layers, and 
 wherein the first and second high-k dielectric layers include zirconium oxide. 
 
     
     
       2. The semiconductor device of  claim 1 , wherein the first and second anti-ferroelectric layers include an anti-ferroelectric hafnium zirconium oxide. 
     
     
       3. The semiconductor device of  claim 1 , wherein the first and second anti-ferroelectric layers have a thickness which is thinner than approximately 30 Å. 
     
     
       4. The semiconductor device of  claim 1 , wherein the hafnium oxide-rich hafnium zirconium oxide has a thickness which is thinner than approximately 30 Å. 
     
     
       5. The semiconductor device of  claim 1 , wherein the high band gap layer has an energy band gap greater than the first and second anti-ferroelectric layers and the first and second high-k dielectric layers. 
     
     
       6. The semiconductor device of  claim 1 , further includes:
 a leakage blocking layer between the second high-k dielectric layer and the second electrode; and 
 an interface control layer over the leakage blocking layer. 
 
     
     
       7. The semiconductor device of  claim 6 , wherein the leakage blocking layer includes a material having a lower dielectric constant and a higher energy band gap than the first and second anti-ferroelectric layers and the first and second high-k dielectric layers. 
     
     
       8. The semiconductor device of  claim 6 , wherein the interface control layer includes a material having a greater electronegativity than the first and second anti-ferroelectric layers and the first and second high-k dielectric layers. 
     
     
       9. The semiconductor device of  claim 1 , further comprising:
 a semiconductor substrate; 
 a transistor including a buried word line structure formed in the semiconductor substrate, and a first source/drain region and a second source/drain region on both sides of the buried word line structure; and 
 a bit line coupled to the first source/drain region of the transistor, 
 wherein the first electrode is coupled to the second source/drain region of the transistor. 
 
     
     
       10. The semiconductor device of  claim 1 , wherein the first and second high-k dielectric layers have a tetragonal crystal structure. 
     
     
       11. The semiconductor device of  claim 1 , wherein the high band gap layer includes aluminum oxide, aluminum-doped zirconium oxide or aluminum-doped hafnium oxide.